skip to content

Cambridge NERC Doctoral Training Partnerships

Graduate Research Opportunities
Brief summary: 
This project will interrogate >50 years of environmental change archived in shells of two commercially and ecologically important species of cockles.
Importance of the area of research concerned: 
Environmental change is widely considered a major threat to the biosphere. Calcifying organisms are thought to be at a significant threat in our changing oceans. In particular, ocean acidification has two potentially deleterious effects; an increased difficulty and cost of shell formation and an accelerated loss and corrosion of shell. Laboratory or field studies of the impact of environmental change are limited by the timescale over which they can be run. However, use of samples from historic collections provide a very valuable source of data to address changes over decades or even centuries. This project will use well documented and localised historic collections, with good contemporary environmental data from sites primarily across the UK but also across Europe, to provide comparative data on shell growth and maintenance of two common and important marine bivalve species. These will be compared to data collected from new collections of extant populations from the same collection sites made in this project.
Project summary : 
Extensive sampling 50 years ago of 2 species of cockles, which are commercially and ecologically important species, from a suite of over 70 localities (UK, Denmark, France, Ireland,) together with habitat data from many. This unique collection provides an excellent opportunity to resample sites and so to research changes in shell structure, composition, production and maintenance over this critical window of climate change. Different sites have experienced different environmental changes, and the number of sites in the study offers unusual power to evaluate the impacts of different factors. We aim to understand both the spatial and temporal variation in calcification over the past five decades of climate change. We also aim to investigate similar cockle species from the Plio-Pleistocene Red Crag Formation to provide a comparative data set over a period of climate cooling.
What will the student do?: 
The student will employ a number of techniques to characterise shells from each sample including a range of morphometric shape analyses, characterization of the microstructure via scanning electron microscopy and thermogravimetric analysis and sclerochronology including detailed growth line analyses and use of oxygen isotopes to help identify annual bands, as well as investigating the occurrence of particular pollutants (e.g. Pb, Sn, etc). They will do field work to collect modern samples from the previously collected sites with environmental data (e.g. water temperatures, salinity etc). Collections will also be made of Pli-Pleistocene fossils from exposures in Suffolk and Essex to investigate very similar cockle species from the Plio-Pleistocene Red Crag Formations. The resulting data analyses will enable the student to write a series of first author scientific papers and a thesis and results will be presented to the science community in conferences and to the public in a range of media. They may also be of use in informing policy makers of impacts of environmental change in a range of aquatic environments.
References - references should provide further reading about the project: 
Telesca L, Michalek K, Sanders T, Peck LS, Thyrring J & Harper EM (2018). Blue mussel shell shape plasticity and natural environments: a quantitative approach. Scientific Reports 8, 2865.
Cross, E., Harper, E.M. & Peck, L.S. (2019). Thicker shells compensate extensive dissolution in brachiopods under future ocean acidification. Environmental Science & Technology 53 (9), 5016-5026
Telesca, L, Peck, L.S., Sanders, T, Thyrring, J., Sehr, M.K. & Harper, E.M. (2019). Plasticity and environmental heterogeneity predict geographic resilience patterns of foundation species to future change. Global Change Biology,
You can find out about applying for this project on the Department of Earth Sciences page.
Prof Elizabeth Harper
Professor Lloyd Peck
Department of Earth Sciences Graduate Administrator